Business Combinations Narrative (Details) (New Affiliates [Member], USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012 affiliate
Business Acquisition [Line Items]
Number of businesses acquired		2
Tax deduction period for goodwill and client relationships amortization expense		15 years
Maximum contingent payments to be made		$ 75,000,000.0
Contingencies amount to be recognized after period of acquisition, minimum		3 years
Contingencies amount to be recognized after period of acquisition, maximum		5 years
New affiliate investments contributed revenue	227,900,000	88,000,000
New affiliate investments contributed earnings	$ 32,100,000	$ 14,500,000
Mutual Fund [Member]
Business Acquisition [Line Items]
Goodwill percentage attributable to segments		67.00%
High Net Worth [Member]
Business Acquisition [Line Items]
Goodwill percentage attributable to segments		32.90%
Institutional [Member]
Business Acquisition [Line Items]
Goodwill percentage attributable to segments		0.10%

Tax deduction period for goodwill and client relationships amortization expense.

No definition available.

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- Definition

Represents the maximum amount of payments to be made by the Company for potential payments under the contingent consideration arrangement including cash and shares.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage of goodwill, attributable to business segment, arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Represents the maximum period in which amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and will be recognized by the entity.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum period in which amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and will be recognized by the entity.

+ References

No definition available.

+ Details

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- Details

Name:	us-gaap_BusinessAcquisitionLineItems
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Data Type:	xbrli:stringItemType
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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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